Maintenance access zones for storage and retrieval systems

ABSTRACT

A maintenance access system for a storage and retrieval system having a storage and retrieval space and automated transport vehicles disposed in the space. The system includes at least one maintenance access control unit associated with a portion of the space, at least one barrier in the space and defining a boundary of the portion of the space and configured to substantially prevent the passage of the vehicles past the at least one barrier, and a controller connected to the control unit, the controller being configured to receive a signal from the at least one control unit for isolating the portion of the space associated with the at least one control unit, where the controller in response to the signal closes the at least one barrier isolating the portion of the space and effects the removal from or shutting down of vehicles within the portion of the space.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. Non-Provisional patentapplication Ser. No. 16/358,506, filed Mar. 19, 2019, which is acontinuation of U.S. Non-Provisional patent application Ser. No.16/018,313, filed Jun. 26, 2018 (now U.S. Pat. No. 10,233,037) which isa continuation of U.S. Non-Provisional patent application Ser. No.15/465,347, filed on Mar. 21, 2017 (now U.S. Pat. No. 10,005,624) whichis a continuation of U.S. Non-provisional patent application Ser. No.15/290,764, filed on Oct. 11, 2016 (now U.S. Pat. No. 9,598,237), whichis a continuation of U.S. Non-provisional patent application Ser. No.14/244,394 filed on Apr. 3, 2014 (now U.S. Pat. No. 9,463,925), which isa continuation of U.S. Non-provisional patent application Ser. No.13/326,565 filed on Dec. 15, 2011 (now U.S. Pat. No. 8,694,152) which isa Non-provisional of and claims the benefit of U.S. Provisional PatentApplication Ser. No. 61/423,308 filed on Dec. 15, 2010, the disclosuresof which are incorporated herein by reference in their entireties.

BACKGROUND 1. Field

The embodiments generally relate to storage and retrieval systems and,more particularly, to maintenance access for autonomous storage andretrieval systems.

BRIEF DESCRIPTION OF RELATED DEVELOPMENTS

Warehouses for storing case units may generally comprise a series ofstorage racks that are accessible by transport devices such as, forexample, fork lifts, carts and elevators that are movable within aislesbetween or along the storage racks or by other lifting and transportingdevices. These transport devices may be automated or manually driven.Generally, when areas of the storage and retrieval system requiremaintenance humans and, for example, the transporting devices and othermoving structures of the storage and retrieval system have anopportunity to occupy substantially the same space within the storageand retrieval system substantially at the same time.

It would be advantageous to provide maintenance access zones that arecapable of isolating areas of the storage and retrieval system whenmaintenance is performed.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and other features of the disclosed embodimentsare explained in the following description, taken in connection with theaccompanying drawings, wherein:

FIG. 1 schematically illustrates an exemplary storage and retrievalsystem in accordance with the embodiments;

FIG. 2 illustrates a schematic plan view of an exemplary storage andretrieval system in accordance with the embodiments;

FIG. 3 illustrates a schematic plan view of another exemplary storageand retrieval system in accordance with the embodiments;

FIG. 4 illustrates a structural portion of a storage and retrievalsystem in accordance with the embodiments;

FIG. 5 is a schematic illustration of an autonomous transport vehicleand a portion of a storage shelf in accordance with the embodiments;

FIGS. 6 and 7 are schematic illustrations of a portion of the storageand retrieval system in accordance with the embodiments;

FIG. 8 is a schematic illustration of a portion of the storage andretrieval system in accordance with the embodiments;

FIGS. 9-9B are schematic illustrations of portions of the storage andretrieval system in accordance with the embodiments;

FIG. 10 is an exemplary flow chart in accordance with the embodiments;and

FIG. 11A is a schematic illustration of another exemplary storagestructure in accordance with the embodiments;

FIG. 11B is a schematic illustration of an autonomous transport inaccordance with the embodiments; and

FIG. 12 is a schematic illustration of a portion of the storage andretrieval system of FIG. 1.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENT(s)

FIG. 1 schematically illustrates an exemplary storage and retrievalsystem in accordance with the embodiments. Although the disclosedembodiments will be described with reference to the embodiments shown inthe drawings, it should be understood that the disclosed embodiments canbe embodied in many alternate forms. In addition, any suitable size,shape or type of elements or materials could be used.

In accordance with the embodiments the storage and retrieval system 100may operate in a retail distribution center or warehouse to, forexample, fulfill orders received from retail stores for case units(where case units as used herein means items not stored in trays, ontotes or on pallets, e.g. uncontained or items stored in trays, totes oron pallets). It is noted that the case units may include cases of items(e.g. cases of soup cans, boxes of cereal, etc.) or individual itemsthat are adapted to be taken off of or placed on a pallet. In accordancewith the exemplary embodiments, shipping cases or case units (e.g.cartons, barrels, boxes, crates, jugs, totes, pallets or any othersuitable device for holding case units) may have variable sizes and maybe used to hold items in shipping and may be configured so they arecapable of being palletized for shipping. It is noted that when, forexample, bundles or pallets of case units arrive at the storage andretrieval system the content of each pallet may be uniform (e.g. eachpallet holds a predetermined number of the same item—one pallet holdssoup and another pallet holds cereal) and as pallets leave the storageand retrieval system the pallets may contain any suitable number andcombination of different items (e.g. each pallet may hold differenttypes of items—a pallet holds a combination of soup and cereal). In theembodiments the storage and retrieval system described herein may beapplied to any environment in which case units are stored and retrieved.

The storage and retrieval system 100 may be configured for installationin, for example, existing warehouse structures or adapted to newwarehouse structures. In the embodiments, the storage and retrievalsystem may include in-feed and out-feed transfer stations 170, 160,multilevel vertical conveyors 150A, 150B (generally referred to hereinas multilevel vertical conveyors 150), a storage structure 130, and anumber of autonomous transport vehicles or robots 110 (referred toherein as “bots”). In the embodiments the storage and retrieval systemmay also include robot or bot transfer stations (as described in, forexample, U.S. patent application Ser. No. 12/757,220, entitled “STORAGEAND RETRIEVAL SYSTEM” and filed on Apr. 9, 2010, the disclosure of whichis incorporated by reference herein in its entirety) that may provide anindirect interface between the bots 110 and the multilevel verticalconveyor 150A, 150B. The in-feed transfer stations 170 and out-feedtransfer stations 160 may operate together with their respectivemultilevel vertical conveyors 150A, 150B for bi-directionallytransferring case units to and from one or more levels of the storagestructure 130. It is noted that while the multilevel vertical conveyorsare described herein as being dedicated inbound or in-feed conveyors150A and outbound or out-feed conveyors 150B, in the embodiments each ofthe conveyors 150A, 150B may be used for both inbound and outboundtransfer of case units/items from the storage and retrieval system. Themultilevel vertical conveyors may be any suitable lifting devices fortransporting case units between levels of the storage and retrievalsystem. It is noted that while multilevel vertical conveyors aredescribed herein in other aspects the conveyors may be any suitableconveyors or transfer/picking devices having any suitable transport pathorientation. Some non-limiting suitable examples of multilevel verticalconveyors can be found in, for example, U.S. Provisional patentapplication entitled “LIFT INTERFACE FOR STORAGE AND RETRIEVAL SYSTEMS”with (Ser. No. 61/423,298) and filed on Dec. 15, 2010 (now U.S. patentapplication Ser. No. 13/327,088 and filed on Dec. 15, 2011), and U.S.patent application Ser. No. 12/757,354, entitled “LIFT INTERFACE FORSTORAGE AND RETRIEVAL SYSTEMS,” (the disclosures of which areincorporated by reference herein in their entireties) and U.S. patentapplication Ser. No. 12/757,220, entitled “STORAGE AND RETRIEVALSYSTEM,” (previously incorporated by reference). For example, themultilevel vertical conveyors may have any suitable number of supportshelves for transporting the case units to a predetermined level of thestorage and retrieval system. The support shelves may have slattedsupports configured to allow fingers of the bots 110 or in-feed/out-feedtransfer stations 170, 160 to pass between the slats for transferringcase units to and from the conveyor. In the embodiments transfer of caseunits between the bots and the multilevel vertical conveyors may occurin any suitable manner.

As may be realized, the storage and retrieval system 100 may includemultiple in-feed and out-feed multilevel vertical conveyors 150A, 150Bthat are accessible by, for example, bots 110 on each level of thestorage and retrieval system 100 so that one or more case unit(s) can betransferred from a multilevel vertical conveyor 150A, 150B to eachstorage space on a respective level and from each storage space to anyone of the multilevel vertical conveyors 150A, 150B on a respectivelevel. The bots 110 may be configured to transfer the case units betweenthe storage spaces and the multilevel vertical conveyors with one pick(e.g. substantially directly between the storage spaces and themultilevel vertical conveyors). By way of further example, thedesignated bot 110 picks the case unit(s) from a shelf of a multilevelvertical conveyor, transports the case unit(s) to a predeterminedstorage area of the storage structure 130 and places the case unit(s) inthe predetermined storage area (and vice versa).

The bots 110 may be configured to place case units, such as the abovedescribed retail merchandise, into picking stock in the one or morelevels of the storage structure 130 and then selectively retrieveordered items for shipping the ordered items to, for example, a store orother suitable location. In the embodiments, the bots 110 may interfacein any suitable manner with the multilevel vertical conveyors 150A, 150Bsuch as through, for example, extension of a transfer arm or effector ofthe bot (which may have fingers for interfacing with slatted supportshelves of the multi-level vertical conveyors) relative to a frame ofthe bot. Suitable examples of bots are described in U.S. patentapplication Ser. No. 12/757,312, entitled “AUTONOMOUS TRANSPORTS FORSTORAGE AND RETRIEVAL SYSTEMS” and filed on Apr. 9, 2010, U.S.Provisional Patent Application entitled “BOT PAYLOAD ALIGNMENT ANDSENSING” (Ser. No. 61/423,220) and filed on Dec. 15, 2010 (now U.S.patent application Ser. No. 13/327,040 filed on Dec. 15, 2011), U.S.Provisional Patent Application entitled “AUTOMATED BOT WITH TRANSFERARM” (Ser. No. 61/423,365) and filed on Dec. 15, 2010 (now U.S. patentapplication Ser. No. 13/326,952 filed on Dec. 15, 2011), U.S.Provisional Patent Application entitled “BOT HAVING HIGH SPEEDSTABILITY” (Ser. No. 61/423,359) and filed on Dec. 15, 2010 (now U.S.patent application Ser. No. 13/326,447 filed on Dec. 15, 2011), and U.S.Provisional Patent Application entitled “AUTOMATED BOT TRANSFER ARMDRIVE SYSTEM” (Ser. No. 61/423,388) and filed on Dec. 15, 2010 (now U.S.patent application Ser. No. 13/326,993 filed on Dec. 15, 2011), thedisclosures of which are incorporated by reference herein in theirentireties.

The storage structure 130 may include multiple levels of storage rackmodules where each level includes an array of storage spaces (arrayed onthe multiple levels and in multiple rows on each level), picking aisles130A formed between the rows of storage spaces, and transfer decks 130B.In the embodiments, each level may also include respective bot transferstations that provide an indirect interface between the bots and themultilevel vertical conveyors. In this exemplary embodiment, the pickingaisles 130A and transfer decks 130B may be arranged for allowing thebots 110 to traverse respective levels of the storage structure 130 forplacing case units into picking stock and to retrieve the ordered caseunits. As may be realized, the storage and retrieval system may beconfigured to allow random accessibility to the storage spaces. Forexample, all storage spaces in the storage structure 130 may be treatedsubstantially equally when determining which storage spaces are to beused when picking and placing case units from/to the storage structure130 such that any storage space of sufficient size can be used to storeitems. The storage structure 130 of the embodiments may also be arrangedsuch that there is no vertical or horizontal array partitioning of thestorage structure. For example, each multilevel vertical conveyor 150A,150B is common to all storage spaces (e.g. the array of storage spaces)in the storage structure 130 such that any bot 110 can access eachstorage space and any multilevel vertical conveyor 150A, 150B canreceive case units from any storage space on any level so that themultiple levels in the array of storage spaces substantially act as asingle level (e.g. no vertical partitioning). The multilevel verticalconveyors 150A, 150B can also receive case units from any storage spaceon any level of the storage structure 130 (e.g. no horizontalpartitioning). In the embodiments the storage and retrieval system maybe configured so that each multilevel vertical conveyor serves apredetermined area of the array of storage spaces.

Referring to FIG. 11A, in another aspect the storage structure may beconfigured such that one or more levels of storage shelves are accessedby but one level of the storage aisle. For example, as described above,each storage aisle includes pairs of tracks 1300 disposed on both sidesof the storage aisle for the bot 110 to travel on. The pairs of tracksare arranged in a vertical stack such that one pair of tracks 1300 (e.g.a storage aisle level 1300L) provides bot 110 access to one or more ofthe vertically stacked storage shelves 600 (e.g. one storage aisle levelis common to multiple storage rack levels). In one aspect each storageaisle level 1300L may provide bot 110 access to but one level of storageshelves 600 while in other aspects each storage aisle level 1300L1 mayprovide bot 110 access to more than one level of storage shelves 600. Instill other aspects some storage aisle levels (or a portion thereof) mayprovide access to one level of storage shelves while other storage aislelevels (or a portion thereof, e.g., in the same or a different storageaisle of the storage structure) may provide access to more than onelevel of storage shelves 600. The storage aisle levels 1300L may bevertically spaced apart (e.g. the vertical distance between the pairs oftracks 1300) by any suitable distance Y1 to allow for the location of atleast one storage level between the storage aisle levels 1300L. Forexemplary purposes only the distance Y1 may be, for example, abouttwenty-four inches while in other examples the distance Y1 may be moreor less than about twenty-four inches. The distance Y2, Y3 between eachstorage shelf 600 may be any suitable distance to allow for case unitsof any suitable size to be placed on the respective storage shelves 600.For exemplary purposes only, the vertical distance Y2 between storageshelves 600F1 and 600F2 may be sufficient for placement of a case unithaving a height of about five inches (or any other suitable height)while in other examples the distance Y2 may be any suitable distance forallowing placement of a case unit having a height of more or less thanabout five inches (or any other suitable height). Also for exemplarypurposes only, the vertical distance Y3 between storage shelves 600F2and 600F3 may sufficient for placement of a case unit having a height ofabout nine inches while in other examples the distance Y3 may be anysuitable distance for allowing placement of a case unit having a heightof more or less than about nine inches. While the distances Y2 and Y3are described above as being different from each other so that therespective storage shelves can accommodate case units of differingheights, in other aspects the distances Y2, Y3 between storage shelves600 may be substantially the same. As an example, a first or base levelshelf 600F1 may be provided closest to the tracks 1300 (or transferdeck/aisle structure) where the bot arm 110A may effect picking/placingof case units 1101 on the base level shelf 600F1 with substantiallylittle or no lift. The base level shelf 600F1 may extend a length of thewhole picking aisle 130A or part of the length of the picking aisle130A. One or more upper pick level shelves 600F2, 600F3 may be providedover the base level shelf 600F1 for at least part of the length of theaisle (in one aspect one or more of the upper pick level shelves 600F2,600F3 may extend substantially the whole length of the picking aisle130A where desired). The depth of the storage levels 600F1-600F3 may besufficient for the picking/placing of case units 1101 with the bot arm110A extension/reach. It is noted that the height of the upper picklevels 600F2, 600F may be varied along the length of the picking aisle130A (e.g. shelf height may be commensurate with storage distribution).For example, in some portions of the picking aisle 130A one or more ofthe upper level storage shelves 600F2, 600F3 may be closer to the baseshelf 600F1 (e.g. to allow placement of taller case units on the uppershelves), while along other portions of the of the picking aisle 130Aone or more of the upper level shelves 600F2, 600F3 may be further awayfrom the base shelf 600F1 to allow taller cases to be placed on thelower shelves. In other aspects other portions of the picking aisle mayhave the base level shelf 600F1 without any of the upper level storageshelves 600F2, 600F3. The multiple storage levels per picking aisletrack 1300 may exploit the storage volume over the base storage level600F1 to provide increased rack storage case density per length of rack.The upper rack levels 600F2, 600F3 may be substantially similar to thebase level rack 600F1 and have, for example, unconstrained case unitsupport for dynamic positioning of the case units. The incremented hatseating surface, of the upper storage levels 600F2, 600F3, formed by theinverted hat 620H1, 620H2 storage structure, similar to that of the baselevel 600F1 (see FIG. 12) is positioned such as by reference to a datum,to allow bot positioning for the base and upper levels 600F1-600F3 witha common bot positioning system in the picking aisles 130A (e.g. thesame positioning system is used by the bot for the base and upperstorage levels 600F1-600F3). In one aspect one or more of the bot 110and storage rack levels 600F1-600F3 may include suitable sensors orother flagging devices to confirm a case height for either the basestorage level 600F1 or one of the upper storage levels 600F2, 600F3 toconfirm the case units 1101 height with a height of the storage rack600F1-600F3 and bot lift for unhindered picking and placing of the caseunit 1101 on the desired storage rack level 600F1-600F3.

Referring also to FIG. 11B, where one or more of the storage aislelevels 1300L provides bot access to at least one level of storageshelves 600 the bot 110 may be configured to transport case units 1101from the storage aisle level to any one of the storage shelf levelsserved by that storage aisle level 1300L. For example, in one aspect thebot may have a lift unit 110L configured to raise and lower a transferarm 110A of the bot 110 in the direction of arrow 1181 so thatpredetermined fingers 110F of the transfer arm 110A may beextended/retracted in the direction of arrow 1182 for transferring thecase units 1101 between the bot 110 and the respective storage shelflevels. The lift unit 110L may be any suitable drive configured to raiseand lower the transfer arm 110A such as, for example, a hydraulic lift,a ball screw mechanism, any suitable linear actuator, a rail system,chain and sprocket system, belt and pulley system or any other suitabledrive system. The transfer arm 110A includes fingers 110F for supportingone or more case units 1101 during transfer of the case units betweenthe bot 110 and a storage shelf 600. In one aspect, the lift unit 110Lmay be configured to lift the transfer arm as a unit while stillallowing the fingers 110F to be vertically movable relative to a frameof the transfer arm 110 and extendible in the direction of arrow 682using a common drive axis as described in, for example, U.S. patentapplication Ser. No. 13/326,952 which is non-provisional of U.S. Ser.No. 61/423,365 filed on Dec. 15, 2010) entitled “Automated Bot withTransfer Arm” filed on Dec. 15, 2011, and U.S. patent application Ser.No. 13/327,040 which is non-provisional of U.S. Ser. No. 61/423,220filed on Dec. 15, 2010) entitled “Bot Payload Alignment and Sensing”filed on Dec. 15, 2011 incorporated herein by reference.

The storage structure 130 may also include charging stations 130C forreplenishing, for example, a battery pack of the bots 110. In theembodiments, the charging stations 130C may be located at, for example,transfer areas 295, 895 (FIGS. 2, 3 and 8) of the transfer deck 130B sothat the bots 110 can substantially simultaneously transfer items, forexample, to and from a multilevel vertical conveyor 150A, 150B whilebeing charged. The bots 110 and other suitable features of the storageand retrieval system 100 may be controlled by any suitable controllersuch as, for example, one or more central system control computers (e.g.control server) 120 through, for example, any suitable network 180. Thenetwork 180 may be a wired network, a wireless network or a combinationof a wireless and wired network using any suitable type and/or number ofcommunication protocols. It is noted that, in the embodiments, thesystem control server 120 may be configured to manage and coordinate theoverall operation of the storage and retrieval system 100 and interfacewith, for example, a warehouse management system 125, which in turnmanages the warehouse facility as a whole. The control server 120 may besubstantially similar to that described in, for example, U.S. patentapplication Ser. No. 12/757,337, entitled “CONTROL SYSTEM FOR STORAGEAND RETRIEVAL SYSTEMS” and filed on Apr. 9, 2010 (the disclosure ofwhich is incorporated by reference herein in its entirety).

Referring also to FIG. 2, an exemplary configuration of the storage andretrieval system 100 is shown. Other suitable exemplary configurationsof storage and retrieval systems can be found in, for example, U.S.Provisional Patent Application entitled “Warehousing Scalable StorageStructure” (Ser. No. 61/423,340) and filed on Dec. 15, 2010 (now U.S.patent application Ser. No. 13/326,674 filed on Dec. 15, 2011), and U.S.patent application Ser. No. 12/757,381, entitled “STORAGE AND RETRIEVALSYSTEM” and filed on Apr. 9, 2010, the disclosures of which areincorporated by reference herein in their entireties. It should beunderstood that in alternate embodiments the storage and retrievalsystem may have any suitable configuration. As can be seen in FIG. 2,the storage and retrieval system 200 is configured, for exemplarypurposes only, as a single-ended picking structure in which only oneside of the system 200 has a transfer section or deck 130B. Thesingle-ended picking structure may be used in, for example, a buildingor other structure having loading docks disposed only on one side of thebuilding. In this example, the storage and retrieval system 200 includestransfer deck(s) 130B and picking aisles 130A that allow bots 110 totraverse an entirety of a level of the storage structure 130 on whichthat bot 110 is located for transporting items between any suitablestorage locations/picking aisles 130A and any suitable multilevelvertical conveyors 150A, 150B (FIG. 1).

The storage and retrieval system 200 may include maintenance accessgateways 210A, 210B that allow, for example, maintenance personnel (e.g.human access) to enter the storage and retrieval system 200 foraccessing any suitable structure or component(s) of the storage andretrieval system. In this example a maintenance access gateway 210A isprovided on one end of the transfer deck. Another maintenance accessgateway may be provided at the ends of the picking aisles 130A oppositethe transfer deck 130B. In the embodiments maintenance access gatewaysmay be provided for each level of the storage and retrieval systemand/or a single maintenance access gateway may serve multiple levels ofthe storage and retrieval system. It should also be understood thatwhile only maintenance access gateways 210A, 210B are shown, the storageand retrieval system may have any suitable number of maintenance accessgateways located at any suitable locations of the storage and retrievalsystem. The maintenance access gateways may provide access to one ormore maintenance access zones each of which is capable of being “lockedout” (e.g. moving storage and retrieval components within the zone arestopped and/or removed from the zone as will be described in greaterdetail below) when maintenance personnel are within the maintenanceaccess zone. In this example, each of the picking aisles may be definedas an individual maintenance access zone and the transfer deck may bedefined as another maintenance access zone. Each of the “aislemaintenance access zones” may be accessible through a respective one ofthe gateways 210B that, in this example, are arranged transverse to theaisles at a back of the storage and retrieval system. The “transfer deckmaintenance access zone” may be accessible through, for example, thegateway 210A located at any suitable location of the transfer deck 130B.As may be realized, in alternate embodiments each of the aisles andtransfer deck may be divided into one or more maintenance access zonesthat are capable of being individually locked out so that at least partof the transfer deck and/or picking aisle is operational (e.g. forstoring and retrieving cases) while a maintenance access zone is lockedout.

Referring to FIG. 3, another exemplary storage and retrieval system 300is shown. The storage and retrieval system 300 may be substantiallysimilar to storage and retrieval system 100 except as otherwise noted.In this example, the storage and retrieval system is illustrated ashaving a double-ended picking structure in which both sides of thesystem 300 have a transfer section or deck 130B1, 130B2. Thedouble-ended picking structure may be used in, for example, a buildingor other structure having loading docks disposed on substantiallyopposite sides of the building. In this example, the storage andretrieval system 300 includes transfer decks 130B1, 130B2 and pickingaisles 130A. A maintenance access gateway 310A is disposed to provideaccess to transfer deck 130B1. Maintenance access gateway 310B isdisposed, for exemplary purposes only, substantially midway betweentransfer decks for providing access to the picking aisles. In thisexample, the maintenance access gateway 310B may be common to allpicking aisles 130A but in alternate embodiments one or more of thepicking aisles may have its/their own maintenance access gatewayseparate from the maintenance access gateway(s) of other picking aisles.In this example, each picking aisle 130A may be divided into twomaintenance access zones (e.g. one zone is on side A of the storagestructure and one zone is on side B of the storage structure) each ofwhich are accessible through the maintenance access gateway 310B. Itshould be understood that in the embodiments, any suitable number ofmaintenance access gateways may be provided at any suitable number oflocations along the length of the picking aisles between the transferdecks 130B1, 130B2 for providing any suitable number of access zoneswithin the picking aisles (e.g. aisle access zones). Also in theembodiments, two maintenance access gateways 310C, 310D may be providedon opposite ends of the transfer deck 130B2. The transfer deck may alsoinclude a shunt 350 that allows bots to traverse between travel lanes351, 352 of the transfer deck 130B2 without travelling the entire lengthof the transfer deck 130B2. The transfer deck 130B2 may be divided intotwo maintenance access zones 360, 361 so that one portion of thetransfer deck 130B2 may remain operational (e.g. for storing andretrieving cases) while the other portion of the transfer deck 130B2 islocked out. As may be realized a boundary of the maintenance accesszones 360, 361 may be located substantially at the shunt 350 so that thebots 110 travelling on the transfer deck 130B2 are able to travel in aloop around the operational portion of the transfer deck while the otherportion of the transfer deck is locked out. In the embodiments, thetransfer deck 130B2 may have any suitable number of shunts for formingany suitable number of maintenance access zones each of which areaccessible through a respective maintenance access gateway or a commonmaintenance access gateway.

As described above, referring to FIGS. 4 and 5, the storage andretrieval systems of the embodiments include vertically stacked storagelevels, each of which include a respective transfer deck 130B (FIG. 1)and picking aisle 130A (FIG. 1). In the embodiments, one transfer deckmay also serve more than one level of picking aisles (e.g. storagelevels) such as through ramps or lifts configured to allow the bots 110to travel between the transfer deck and the more than one storage level.The storage structure 130 may include any suitable number of storagemodules 501, 502, 503 each having any suitable number of storage bays510, 511. Each of the storage bays 510, 511 may hold the picking stockon storage shelves 600 that are separated by the picking aisles 130A. Inthe embodiments the storage bays 510, 511 and storage shelves 600 may besubstantially similar to those described in, for example, U.S. patentapplication Ser. No. 12/757,220, entitled “STORAGE AND RETRIEVALSYSTEM,” and U.S. patent application Ser. No. 12/757,381, entitled“STORAGE AND RETRIEVAL SYSTEM” (both of which being previouslyincorporated by reference).

It is noted that in one exemplary embodiment the storage modules 501,502, 503 may include vertical supports 612 and horizontal supports 610,611, 613 that are joined to form the storage bays 510, 511. In theembodiments one or more of the vertical supports 612 and horizontalsupports 610, 611, 613 may be configured to allow for adjusting theheight or elevation of the storage shelves 600 and/or aisle floors 130F(FIGS. 2, 3 and 6) relative to, for example, each other and a floor ofthe facility in which the storage and retrieval system is located. Inthe embodiments, one or more of the storage shelves and floors may befixed in elevation. As can be seen in FIG. 4, storage module 501 isconfigured as an end module having, for example, about half the width ofthe other storage modules 502, 503. As an example, the end module 501may have a wall located on one side and the picking aisle 130A locatedon the opposite side. The depth D1 of end module 501 may be such thataccess to the storage shelves 600 on module 501 is achieved by thepicking aisle 130A located on but one side of the storage module 501,whereas the storage shelves 600 of modules 502, 503 may be accessed bypicking aisles 130A located on both sides of the modules 502, 503allowing for, as an example, the storage modules 502, 503 having a depthsubstantially twice that of the depth D1 of storage module 501.

In the embodiments, as can be seen in, for example, FIGS. 5 and 6,tracks 1300 may be fixed to one or more of the vertical and horizontalsupports 612, 610, 611, 613 of the storage structure in any suitablemanner such that the bot straddles adjacent tracks 1300 for traversing apicking aisle 130A. As can be seen in FIGS. 5 and 6 one or more levels670-675 of the picking aisles 130A may be substantially verticallyunobstructed by floors 130F (e.g. one or more of the picking aisles donot have floors). The absence of floors 130F on each picking level670-675 may allow maintenance personnel to walk or otherwise travel downthe picking aisles where the height between each storage level wouldotherwise substantially prevent the maintenance personnel fromtraversing the picking aisles 130A. In the embodiments, any suitablecarts or dollies may be provided (in lieu of or in addition to thefloors) where the carts or dollies straddle the adjacent tracks in amanner substantially similar to that described above with respect to thebots 110 or ride along the floors 130F so that the maintenance personnelmay ride on the carts or dollies for traversing the picking aisles.

As can be seen in FIG. 6, for exemplary purposes only, an end view ofseveral picking aisles 130A1-130A3 each having multiple levels 670-675is shown (e.g. looking down the aisles towards the transfer deck). Inthis example, levels 672 and 675 include aisle floors 130F for providingmaintenance access to one or more levels of the picking aisle 130A2. Theaisle floor 130F on level 675 may provide access to, for example,storage levels 673-675 (e.g. maintenance access zone Z1) and the aislefloor 130F on level 672 may provide access to, for example, storagelevels 670-672 (e.g. maintenance access zone Z2). It should beunderstood that the levels on which the aisle floors 130F are locatedare exemplary only and that in alternate embodiments any suitable numberof floors may be provided at any number of storage levels for providingmaintenance access within the picking aisles. It should also beunderstood that the storage levels 670-675 may be grouped together ornot grouped together in any suitable manner for forming one or moremaintenance access zones.

Access to each level 672, 675 having an aisle floor 130F may be providedin any suitable manner using any suitable access device 810 (FIG. 8) ofa corresponding maintenance access gateway (210B, FIGS. 2 and 310B, FIG.3). In one example where the storage structure is a single-endedstructure the access device 810 may be one or more platforms, ladders,elevators or other lifting devices located at an end of a respectiveaisle at for example, maintenance access gateway 210B. In anotherexample where the storage structure is a double-ended structure, inaddition to or in lieu of having access located at the ends of thestructure as described above with respect to the single-ended structure,the access device 810 may be located between transfer decks 130Badjacent a respective aisle at for example, maintenance access gateway310B or at any other suitable location of the storage and retrievalsystem. The access device 810 of the maintenance access gateway 210B,310B may be a rack or platform structure extending, for example, theentire width W (e.g. transverse to a length of the picking aisles) or aportion of the width W of the storage structure where the rack structureincludes, for example, a floor corresponding to each of the aisle floors130F and one or more flights of stairs, ladders, or other structureallowing maintenance personnel to traverse between the floors of therack structure. It is noted that in the embodiments any suitable deviceor structure may be used to provide maintenance personnel access to theaisle floors 130F.

Referring to FIG. 7 one or more suitable barriers 700, 701 may beprovided at, for example, the end of the picking aisle 130 opposite thetransfer deck (where the storage structure is a single-ended structure)and/or substantially within or adjacent the maintenance access gateway310B (where the storage structure is a double-ended structure) tosubstantially prevent, for example, a bot 110 from exiting a pickingaisle and entering, for example, the maintenance access gateway (210B,310B, FIGS. 2 and 3). As may be realized, the barriers placed at theends of the picking aisles (e.g. opposite the transfer deck) in, forexample, the single-ended picking structure may also substantiallyprevent moving bots 110 from exiting the picking aisles during operationof the storage and retrieval system 100 regardless of whether or notthere is a maintenance access gateway located at the end of the pickingaisle. As may be realized, the barriers in maintenance access gateway310B of the double-ended picking structure may be removed from, forexample, at least the picking aisles 130A that are not locked out toallow bots 110 full access to the both sides A, B of the picking aisles130A when the storage and retrieval system is operational for storingand retrieving cases.

The one or more barriers 700, 701 may be in the form of one or more netsbut the barriers may also be in the form of bars (substantially similarto those described below), screens (substantially similar to the netsbut having a more substantially rigid framed structure), or any othersuitable barrier for substantially preventing the passage of bots 110through the barrier. In one example, a barrier 700, 701 may be providedfor each group of storage levels 670-675 served by a respective aislefloor 130F. For example, a barrier 700 may be provided for maintenanceaccess zone Z1 and barrier 701 may be provided for maintenance accesszone Z2. The barriers 700, 701 may be removably or movably attached to,for example, one or more of the vertical or horizontal members 610-612of the storage structure so that the barrier may be at least partiallyremoved or opened to allow maintenance personnel to enter, for example,the picking aisle 130A2. For example, where the barrier 700, 701 is inthe form of a net, the net may be fastened to the vertical and/orhorizontal members 610-612 using clips, or other removable fasteners sothat at least a portion of the net may be moved away from the storagestructure allowing access into the picking aisle 130A2. Where thebarrier 700, 701 is in the form of bars or screens a hinged or othermoveable connection may be used so that the bars or screens functionsubstantially as doors or gates to allow access into the picking aisles130A. The barriers 700, 701 may be configured to allow access into thepicking aisles in any suitable manner.

It is noted that where the barriers 700, 701 are used in a double-endedstorage structure, such as within maintenance access gateway 310B (FIG.3) the barriers 700, 701 may be provided for one or more levels ofpicking aisles only when those picking aisles are locked out (e.g. thebarrier is not present during operation of the associated picking aislelevels when those picking aisle levels are operational for storing andretrieving cases). In one example, referring briefly to FIG. 3, ifmaintenance personnel were accessing picking aisle 130A4 from the leftof the storage and retrieval system 300 through maintenance accessgateway 310B the movable barriers may be automatically positioned, e.g.upon a locking out of the desired level(s) of picking aisle 130A4, toblock one or more sides of the maintenance access gateway for thedesired storage level(s) (e.g. a barrier would be placed in any pickingaisle 130A1-130A4 through which the maintenance personnel would travelto reach the locked out aisle). The maintenance access gateway 310B maybe configured in any suitable manner to provide access to any desiredstorage levels of any desired aisle without blocking other pickingaisles. The barriers may also be moved into position to block thedesired levels of one or more picking aisles in any suitable manner.

Referring to FIGS. 8 and 9, examples of barriers that may be used, forexample, in any suitable areas of the storage and retrieval system 100that are, for example, substantially inaccessible to maintenancepersonnel when the system is operational are shown. These barriers maybe actuated for blocking a bot pathway within the storage and retrievalsystem 100 when for example, a predetermined maintenance access zone islocked out and before maintenance personnel enter the locked outmaintenance access zone (e.g. to substantially prevent bots 110 fromentering the locked out maintenance access zone. The barriers may alsobe configured to allow maintenance personnel to actuate or otherwise putin place the barriers when the maintenance personnel are located withinthe maintenance access zone. In FIG. 8 one storage level of, forexample, the storage and retrieval system 100 is shown but it should beunderstood that one or more levels of the storage and retrieval systemmay include barriers substantially similar to those described herein.Barriers 800-803 may be placed at any suitable location within thestorage and retrieval system 100 and those barriers 800-803 shown inFIG. 8 are shown in exemplary locations only. It should be realized thatthe entrance/exit to each picking aisle 130A and each transfer area 895may have a barrier located thereat. It should also be realized thatwhile only one barrier 803 is shown on the transfer deck 130B, otherbarriers may be located on the transfer deck for separating the transferdeck 130B into any suitable number of maintenance access zones. Forexemplary purposes only maintenance access zone Z3 is shown as includingpicking aisle 130A and as described above may extend above or below thestorage level shown in FIG. 8 to include additional storage levels in amanner substantially similar to that shown in FIG. 6 with respect tomaintenance access zones Z1 and Z2. Maintenance access zone Z5 is shownas including a transfer area 895 for a multilevel vertical conveyor 150.It is noted that with respect to the multilevel vertical conveyors 150the maintenance access zone Z5 may extend to all of the transfer areas(e.g. vertical stack of transfer areas) associated with a particularmultilevel vertical conveyor 150 being locked out so that the multilevelvertical conveyor 150 is inoperable or turned off when maintenancepersonnel are located in the transfer area 895 corresponding to themultilevel vertical conveyor 150. Maintenance access zone Z4 is shown asincluding a portion of the transfer deck 130B. In a manner similar tothat described above with respect to FIG. 3, the maintenance accesszones Z4 on the transfer deck 130B may be arranged so that at least aportion of the transfer deck 130B remains operational (e.g. for storingand retrieving cases) for allowing bots 110 to traverse the deck foraccessing picking aisles 130A and transfer areas 895 associated with theoperational portion of the transfer deck 130B.

The barriers 800-803 may be any suitable barriers configured tosubstantially prevent the passage of, for example, a bot 110 through(including passage above or below) the barrier. It is noted that whilesome exemplary barriers 901, 902, 903, 950 are described with respect topicking aisle 130A it should be understood that substantially similarbarriers may also be located on the transfer deck 130B (see barrier 803)and at the entrance/exit of the transfer areas 895 (see barriers 801,802).

In the embodiments the barrier 902 may be a substantially bar or gatelike barrier that linearly raises and lowers for blocking, for example,an entrance/exit of for example, a storage level of picking aisle 130A.The barrier 902 may be raised or lowered in the direction of arrow 997in any suitable manner and may be movably mounted in any suitable mannerto, for example, vertical supports 612 of the storage and retrievalsystem 100. As may be realized when the barrier 902 is retracted it maybe lowered below a surface of the transfer deck 130B and/or rails 1300on which the bot 110 travels.

In the embodiments the barrier 901 may be a pivotable barrier. Thebarrier 901 may be substantially similar to barrier 902 but instead ofbeing substantially linearly raised and lowered. The barrier 901 may bepivotally raised from a substantially horizontal orientation to asubstantially vertical orientation in the direction of, for example,arrow 998. In this example, when the barrier is in a horizontalorientation the barrier is located partially within the transfer deckand may be substantially flush with or below a surface of the transferdeck 130B and/or picking aisle 130A on which the bot 110 travels. Thebarrier 901 may also be offset from the transfer deck 130B so that whenin the horizontal orientation the barrier is located substantiallyentirely within the picking aisle. In one example, the direction inwhich the barrier 901 pivots may be such that if a bot 110 impacts thebarrier 901 when trying to enter the picking aisle 130A, the barriersubstantially cannot be pivoted to the horizontal position by the bot110. The barrier 901 may also pivot in any suitable direction.

In the embodiments the barrier 903 may be in the form of one or morevertically pivotal barriers 903A, 903B. In this example the barrier 903is shown as having two opposingly pivotable members 903A, 903B thebarrier 903 may also have more or less than two vertically pivotablemembers. The one or more pivotable members may also be horizontallypivotable rather than vertically pivotable in a manner substantiallysimilar to a door or gate. Each pivotable member 903A, 903B may bepivotally mounted in any suitable manner to a respective verticalsupport 612 of the storage and retrieval system and be drivingly pivotedin the direction of arrow 999A, 999B in any suitable manner between theopen (e.g. bots are able to pass) and closed (bots are not able to pass)positions.

Referring also to FIGS. 9A and 9B, where screens, nets or other suitableflexible barriers are used, the barrier 950 may be rolled up around, forexample, one or more drums 952 (or other suitable member capable ofholding the barrier) and connected to one or more drive units 951through a connecting member 951C. In one example the one or more drums652 may be located substantially beneath the surfaces of the rails 1300and the transfer deck 130B on which the bot 110 travels (e.g. on astorage level having a floor 130F, FIGS. 6 and 7) and the one or moredrive units 951 may be located towards a top of a respective maintenanceaccess zone (see e.g. zones Z1, Z2 in FIG. 6). In other examples the oneor more drums 652 may be located substantially beneath the surfaces ofthe rails 1300 and the transfer deck 130B on which the bot 110 travelsfor each of the storage levels and the one or more drive units 951 maybe located towards a top of each respective storage level. It is notedthat the locations of the one or more drive units 951 and the one ormore drums 952 may be reversed. The one or more drive units 951 mayoperate to retract the connecting member 951C in the direction of arrow994. The connecting member may be attached in any suitable manner to thebarrier 950 so that as the connecting member 951C is retracted thebarrier 950 is unrolled from the drum 952 to so that the barrier spanssubstantially from the bot travel surfaces of a respective storage level(or of a storage level having a floor 130F) to substantially a top of arespective storage level (or substantially a top of a respectivemaintenance access zone) in a manner substantially similar to that shownin FIG. 7.

It should be understood that the barriers described herein are exemplaryonly and in alternate embodiments the barriers may be any suitablebarriers that operate in any suitable manner. It should also be realizedthat the types of barrier used in the storage and retrieval system donot have to be uniform and that different types of barriers may be usedin different areas of the storage and retrieval system.

Referring again to FIGS. 6 and 8, each maintenance access zone Z1-Z5 mayhave a control unit 680, 681. The control unit 680, 681 may be incommunication with, for example, control server 120 (FIG. 1) in anysuitable manner such as through a wired or wireless communicationnetwork. It should be understood that while only two control units 680,681 are shown with respect to maintenance access zones Z1, Z2 the othermaintenance access zones may include substantially similar controlunits. It should also be understood that while the control units 680,681 are shown as being located at an entrance to the maintenance accesszone (e.g. in FIG. 6 the entrance may be at the end of the pickingaisles) the control units may be centrally located. Each control unitmay include a switch 660. The switch may be configured such that onceactivated by a maintenance person a part of the switch (or other featureof the control unit) is removed from the control unit 680, 681 tosubstantially prevent deactivation of the switch by other maintenancepersonnel (e.g. the switch cannot be deactivated without replacing theremoved part of the switch/control unit). In other examples the switchmay include a “lock out” feature through which a locking device may beinserted through the switch and a fixed portion of, for example, thecontrol unit housing so prevent deactivation of the switch (e.g. todeactivate the switch the locking device has to be removed). It shouldbe understood that the switch may have any suitable configuration.

Referring to FIGS. 6, 8 and 10 in operation a maintenance personactivates the switch 660 of a desired maintenance access zone Z1-Z5(FIG. 10, Block 1000). Upon activation of the switch 660 a communicationsignal is sent from the respective control unit 680, 681 to, forexample, the control server 120 (FIG. 1). The control server 120 maysend instructions to any bots 110 located within the desired maintenanceaccess zone Z1-Z5 to exit or otherwise leave the desired maintenanceaccess zone. If an operational bot 110 is not able to leave the desiredmaintenance access zone (e.g. due to a malfunction of the bot, ablockage in the picking aisle, etc.) the control server 120 may effectthe shutting down of the bot 110. In addition to or in lieu ofinstructing the operational bots 110 to leave the desired maintenanceaccess zone the control server may effect a shutting down of the bots110 within the maintenance access zone (e.g. bots that are carryingcases may leave the zone while bots that are not carrying cases may shutdown). If the desired maintenance access zone also includes movingcomponents of the storage and retrieval system, such as for example, themultilevel vertical conveyors 150, the control server 120 may also sendinstructions to the multilevel vertical conveyor(s) within the desiredmaintenance access zone Z1-Z5 for stopping or otherwise shutting downthe multilevel vertical conveyor(s). (FIG. 10, Block 1001). The controlserver 120 may effect the placement of the barriers 800-803 associatedwith the desired maintenance access zone Z1-Z5 in any suitable manner(FIG. 10, Block 1002). For example, the control server 120 may effectactivation of any suitable drive units for rotating, pivoting,unrolling, etc. the barriers 800-803 (e.g. as described above withrespect to FIGS. 9-9B) so that the activated barriers substantiallyblock the entrance/exit of the desired maintenance access zone Z1-Z5 tosubstantially prevent bots 110 from entering the desired maintenanceaccess zone Z1-Z5. The barriers, such as nets 700, 701 (FIG. 7) locatedbetween the maintenance access gateways 210A, 210B, 310A, 310B, 310C(FIGS. 2 and 3) which provide access to the maintenance access zonesZ1-Z5 may be removed or otherwise opened to allow maintenance personnelto enter the desired maintenance access zone Z1-Z5 (FIG. 10, Block1003). In the embodiments the opening of the barriers 700, 701 forallowing maintenance personnel to enter the maintenance access zone maybe performed by the maintenance personnel and/or the barriers 700, 701may be automated (in a manner substantially similar to that describedabove with respect to FIGS. 9-9B) such that the barriers 700, 701 areopened substantially after the barrier(s) 800-803 are in place forsubstantially preventing bots from entering the maintenance access zone.It should be understood that the barriers may be opened or removed toallow access into or from a respective maintenance access zone in anysuitable manner.

In accordance with a first aspect of the disclosed embodiment amaintenance access system for a storage and retrieval space andautomated transport vehicles disposed in the storage and retrieval spaceis provided. The maintenance access system includes at least onemaintenance access control unit associated with a portion of the storageand retrieval space, at least one barrier located in the storage andretrieval space and defining a boundary of the portion of the storageand retrieval space, the at least one barrier being configured tosubstantially prevent the passage of the automated transport vehiclespast the at least one barrier, and a controller connected to themaintenance access control unit, the controller being configured toreceive a signal from the at least one maintenance access control unitfor isolating the portion of the storage and retrieval space associatedwith the at least one maintenance access control unit, where thecontroller in response to the signal closes the at least one barrierisolating the portion of the storage and retrieval space and effects theremoval from or shutting down of autonomous transport vehicles withinthe portion of the storage and retrieval space.

In accordance with the first aspect of the disclosed embodiment, theportion of the storage and retrieval space forms a maintenance accesszone including at least one picking aisle of the storage and retrievalspace where the at least one picking aisle is arranged in a verticalstack of picking aisles.

In accordance with the first aspect of the disclosed embodiment, theportion of the storage and retrieval space forms a maintenance accesszone including a transfer deck of the storage and retrieval space, wherethe transfer deck provides the autonomous transport vehicles access toone or more picking aisles and/or one or more multilevel verticalconveyor transfer areas.

In accordance with the first aspect of the disclosed embodiment, theportion of the storage and retrieval system space forms a maintenanceaccess zone including a multilevel conveyor transfer area where themultilevel conveyor transfer area allows the autonomous transportvehicles to transfer cases between the multilevel vertical conveyor andthe picking aisles.

In accordance with a first sub-aspect of the first aspect of thedisclosed embodiment, the storage and retrieval space includes multiplestorage levels, each level including picking aisles, a transfer deckcommon to each picking aisle and multilevel vertical conveyor transferareas connected to the transfer deck. The maintenance access systemfurther including at least one barrier located at one or more of an endof at least one of the picking aisles, an entrance/exit of themultilevel vertical conveyor transfer areas and within the transferdeck.

In accordance with the first sub-aspect of the first aspect of thedisclosed embodiment, the barriers include one or more of nets, fencesand screens.

In accordance with the first sub-aspect of the first aspect of thedisclosed embodiment, the barriers are motorized barriers that areactuated to substantially block the one or more of the end of at leastone of the picking aisles, the entrance/exit of the multilevel verticalconveyor transfer areas and at least portions of the transfer deck.

In accordance with the first aspect of the disclosed embodiment, theportion of the storage and retrieval space forms a maintenance accesszone the includes multiple picking aisles arranged in a vertical stack,where the picking aisle at the bottom of the stack includes a floor andthe picking aisles above the picking aisle at the bottom of the stackwithin the maintenance access zone are substantially floorless.

In accordance with a second aspect of the disclosed embodiment a storageand retrieval system includes a multilevel storage structure including aplurality of storage locations arranged on sides of picking aisles wherethe picking aisles are connected to each other and at least onemultilevel vertical conveyor by a transfer deck; at least one autonomoustransport vehicle configured to travel along the picking aisles andtransfer deck for transferring case units between the storage locationsand the at least one conveyor; and a maintenance access system includingvertically stacked maintenance access zones disposed coincident with thepicking aisles, where each maintenance access zone provides access to atleast multiple levels of picking aisles and storage locationscorresponding to the multiple levels of picking aisles.

In accordance with the second aspect of the disclosed embodiment, themultiple levels of picking aisles are arranged in a vertical stack andthe picking aisle at the bottom of the stack includes a floor and thepicking aisles above the picking aisle at the bottom of the stack for arespective maintenance access zone are substantially floorless.

In accordance with a first sub-aspect of the second aspect of thedisclosed embodiment, the storage and retrieval system further includesat least one maintenance access control unit; at least one barriercorresponding to a respective maintenance access zone, the at least onebarrier being configured to substantially prevent the passage of theautomated transport vehicles past the at least one barrier; and acontroller connected to the maintenance access control unit, thecontroller being configured to receive a signal from the at least onemaintenance access control unit for isolating a portion of the storageand retrieval system associated with the at least one maintenance accesscontrol unit where the controller effects the removal from or shuttingdown of autonomous transport vehicles within the portion of the storageand retrieval system.

In accordance with a first sub-aspect of the second aspect of thedisclosed embodiment, each of the at least one multilevel verticalconveyor includes a transfer area and the at least one barrier isdisposed at one or more of an end of at least one of the picking aisles,an entrance/exit of the multilevel vertical conveyor transfer area andwithin the transfer deck.

In accordance with a first sub-aspect of the second aspect of thedisclosed embodiment, the at least one barrier includes one or more ofnets, fences and screens.

In accordance with a first sub-aspect of the second aspect of thedisclosed embodiment, the at least one barrier comprises at least onemotorized barrier that is actuated to substantially block the one ormore of the end of at least one of the picking aisles, the entrance/exitof the multilevel vertical conveyor transfer areas and at least portionsof the transfer deck.

In accordance with the second aspect of the disclosed embodiment, thestorage and retrieval system further includes at least one maintenancepersonnel cart configured to allow maintenance personnel to traverse themaintenance access zones.

In accordance with the second aspect of the disclosed embodiment, thetransfer deck comprises multiple maintenance access zones configuredsuch that a portion of the transfer deck associated with one maintenanceaccess zone can be disabled while another portion of the transfer deckassociated with another maintenance access zone remains operational.

It should be understood that the exemplary embodiments disclosed hereincan be used individually or in any suitable combination thereof. Itshould also be understood that the foregoing description is onlyillustrative of the embodiments. Various alternatives and modificationscan be devised by those skilled in the art without departing from theembodiments. Accordingly, the present embodiments are intended toembrace all such alternatives, modifications and variances that fallwithin the scope of the appended claims.

What is claimed is:
 1. A human access system for a storage and retrievalsystem having a storage and retrieval space and automated transportvehicles disposed in the storage and retrieval space, the human accesssystem comprising: at least one human access control unit associatedwith a portion of the storage and retrieval space, the portion of thestorage and retrieval space having at least one store shelf; at leastone control device located in the storage and retrieval space anddefining a boundary of the portion of the storage and retrieval space,the at least one control device being configured to stop the passage ofthe automated transport vehicles past the at least one control device;and a controller connected to the human access control unit, thecontroller being configured to receive a signal from the at least onehuman access control unit for isolating the portion of the storage andretrieval space associated with the at least one human access controlunit; wherein in response to the signal, the controller: isolates theportion of the storage and retrieval space with the control device thatstops automated transport vehicles from entering a human access zone,the human access zone is defined by the at least one store shelf, thehuman access zone including at different levels within the portion ofthe storage and retrieval space, and effects routing of operativeautomated transport vehicles away from the human access zone, and stopsautonomous transport vehicles within the human access zone, whereincontinued operation of autonomous transport vehicles is allowed outsidethe human access zone.
 2. The human access system of claim 1, whereinthe human access zone includes at least one picking aisle of the storageand retrieval system, wherein the at least one picking aisle is arrangedin a vertical stack of picking aisles.
 3. The human access system ofclaim 1, wherein the human access zone includes a transfer deck of thestorage and retrieval system, wherein the transfer deck provides theautonomous transport vehicles access to one or more picking aislesand/or one or more lift transfer areas.
 4. The human access system ofclaim 1, wherein human access zone includes a lift transfer area,wherein the lift transfer area allows the autonomous transport vehiclesto transfer cases between the lift and the picking aisles.
 5. The humanaccess system of claim 1, wherein: the human access zone includesmultiple picking aisles arranged in a vertical stack, wherein thepicking aisle at a bottom of the stack includes a floor, and the pickingaisles above the picking aisle at the bottom of the stack within thehuman access zone are substantially floorless.
 6. The human accesssystem of claim 1, wherein: the storage and retrieval space includes:multiple storage levels, each level including picking aisles, a transferdeck common to each picking aisle, and lift transfer areas connected tothe transfer deck; wherein the at least one control device is located atone or more of an end of at least one of: the picking aisles, anentrance/exit of the lift transfer areas, and portions of the transferdeck.
 7. The human access system of claim 6, wherein the at least onecontrol device includes one or more of nets, fences and screens.
 8. Thehuman access system of claim 6, wherein the at least one control devicecomprises at least one motorized control device that is actuated tosubstantially block the one or more of the end of at least one of: thepicking aisles, the entrance/exit of the lift transfer areas, and theportions of the transfer deck.
 9. A method of operating an automatedwarehouse system comprising: providing a storage and retrieval spacewith storage locations, a portion of the storage and retrieval spacehaving at least one store shelf; providing at least one autonomoustransport vehicle that travels within the storage and retrieval space;disposing human access zones, each human access zone having at least onehuman access control unit associated with the at least one store shelfat different levels within the portion of the storage and retrievalspace; providing a control device located in the storage and retrievalspace, the control device defining a boundary of the portion of thestorage and retrieval space, the at least one control device beingconfigured to stop the passage of the automated transport vehicles pastthe at least one control device; and signaling, with a controllercommunicably connected to the control device, a status change of the atleast one human access control unit to isolate the portion of thestorage and retrieval space associated with the human access controlunit; wherein in response to the signal from the controller, the atleast one autonomous transport vehicle within a corresponding humanaccess zone stops, while other autonomous transport vehicles outside ofthe corresponding human access zone continue operation in the storageand retrieval space outside the corresponding human access zone.
 10. Themethod of claim 9, further comprising providing the at least oneautonomous transport vehicle with a transfer arm configured to transferitems to and from the storage locations of the storage and retrievalspace.
 11. The method of claim 9, further comprising transferring caseunits to and from the storage locations of the storage and retrievalspace with the at least one autonomous transport vehicle.
 12. The methodof claim 9, further comprising providing the at least one autonomoustransport vehicle access, with a transfer deck, to at least one of oneor more picking aisles and one or more vertical lift transfer areasdisposed in the storage and retrieval space.
 13. The method of claim 9,further comprising transferring items between a vertical lift and thestorage locations of the storage and retrieval space with the at leastone autonomous transport vehicle at a vertical lift transfer area. 14.An automated warehouse system comprising: a storage and retrieval spacewith storage locations, a portion of the storage and retrieval spacehaving at least one store shelf; at least one autonomous transportvehicle that travels within the storage and retrieval space; humanaccess zones each having at least one human access control unitassociated with the at least one store shelf, each of the human accesszones include different levels within the portion of the storage andretrieval space; a control device located in the storage and retrievalspace, the control device is configured to define a boundary of theportion of the storage and retrieval space, the control device isfurther configured to stop the passage of the automated transportvehicles past the at least one control device; and a controllercommunicably connected to the control device, the controller beingconfigured to signal a status change of the at least one human accesscontrol unit to isolate the portion of the storage and retrieval spaceassociated with the human access control unit; wherein in response tothe signal from the controller, the at least one autonomous transportvehicle within a corresponding human access zone stops while otherautonomous transport vehicles outside the corresponding human accesszone continue operation in the storage and retrieval space outside thecorresponding human access zone.
 15. The automated warehouse system ofclaim 14, wherein the at least one autonomous transport vehicle includesa transfer arm configured to transfer items to and from the storagelocations of the storage and retrieval space.
 16. The automatedwarehouse system of claim 14, wherein the at least one autonomoustransport vehicle is configured to transfer case units to and from thestorage locations of the storage and retrieval space.
 17. The automatedwarehouse system of claim 14, wherein the at least one autonomoustransport vehicle is configured to access, via a transfer deck, at leastone of one or more picking aisles and one or more vertical lift transferareas disposed in the storage and retrieval space.
 18. The automatedwarehouse system of claim 14, wherein the at least one autonomoustransport vehicle is configured to transfer items between a verticallift and the storage locations of the storage and retrieval space at avertical lift transfer area.